Climate change impact on the energy performance of residential buildings in Portugal

18:00 Tuesday 28 May




Cristina Andrade (Portugal) 1,2,3; Sandra Mourato (Portugal) 4,5; João Ramos (Portugal) 4,6

1 - Polytechnic Institute of Tomar, (NHRC.ipt) Natural Hazards Research Center, Tomar, Portugal; 2 - Centre for the Research and Technology of Agro-Environmental and Biological Sciences (CITAB), University of Trás-os-Montes e Alto Douro, Vila Real, Portugal; 3 - University of Aveiro, CESAM, Aveiro, Portugal; 4 - School of Technology and Management, Polytechnic Institute of Leiria, Portugal; 5 - ICAAM - Instituto de Ciências Agrá rias e Ambientais Mediterrânicas, Escola de Ciências e Tecnologia, Universidade de évora, Portugal.; 6 - Institute for Systems Engineering and Computers at Coimbra, INESC Coimbra, Portugal

Under projected future climate change, relevant impacts can be expected, therefore identify sectors in which these impacts are likely to increase should be an effective strategy for managing future climate risks. Commonly the climate policies in the energy sector are focused on emission mitigation, although is increasing awareness on the climate vulnerability and adaptation needs of the energy sector. Recent reports generated a lot of interests in having a better understanding of the energy use characteristics in buildings, especially their correlations with the prevailing weather conditions. Buildings typically have a long life span, lasting for 50 years or more. It is, therefore, important to analyze how buildings will respond to climate change in the future, and assess the likely changes in energy use.

In the present work the potential effects of climate change on future changes of heating energy demand in the household sector, due to heat transfer through the building envelopes, were investigated. Heating Degree Day (HDD) method was used, for the 1961-2050 period, over Portugal, with several regional climate models. HDD is a quantitative indicator that reflects the demand for energy requirements to heat a building at a specific location and is considered to be directly proportional to the heating requirements. HDD (derived over winter months) is computed based on the cumulated daily air temperature deviations below a given temperature threshold value (in this study 18ºC), which is known as the basic temperature.

The evolution of the HDD indicator has been analyzed on three different periods: 1961-1990, 1981-2010 and 2021-2050. The temperature data was retrieved from five high-resolution bias-adjusted EURO-CORDEX 0.11_ (ALADIN53, HIRHAM5, REMO2009, RACMO22E and WRF331F) simulations for two emission representative concentration pathways (RCP4.5 and RCP8.5).

Significant decreases in HDD are projected under the climate change scenario. It can be concluded that the energy performance of a residential building is likely to be affected by climate change over its useful life. Overall, given the lifetime of a building, the impacts of climate change should be an integral component in the design of energy efficient residential buildings and in the future trends of building envelope requirements.